%%%---------------------------------------------------------------------- %%% File : mod_carboncopy.erl %%% Author : Eric Cestari %%% Purpose : Message Carbons XEP-0280 0.8 %%% Created : 5 May 2008 by Mickael Remond %%% Usage : Add the following line in modules section of ejabberd.yml: %%% {mod_carboncopy, []} %%% %%% %%% ejabberd, Copyright (C) 2002-2016 ProcessOne %%% %%% This program is free software; you can redistribute it and/or %%% modify it under the terms of the GNU General Public License as %%% published by the Free Software Foundation; either version 2 of the %%% License, or (at your option) any later version. %%% %%% This program is distributed in the hope that it will be useful, %%% but WITHOUT ANY WARRANTY; without even the implied warranty of %%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU %%% General Public License for more details. %%% %%% You should have received a copy of the GNU General Public License along %%% with this program; if not, write to the Free Software Foundation, Inc., %%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. %%% %%%---------------------------------------------------------------------- -module (mod_carboncopy). -author ('ecestari@process-one.net'). -protocol({xep, 280, '0.8'}). -behavior(gen_mod). %% API: -export([start/2, stop/1]). -export([user_send_packet/4, user_receive_packet/5, iq_handler2/3, iq_handler1/3, remove_connection/4, is_carbon_copy/1, mod_opt_type/1]). -include("ejabberd.hrl"). -include("logger.hrl"). -include("jlib.hrl"). -define(PROCNAME, ?MODULE). -callback init(binary(), gen_mod:opts()) -> any(). -callback enable(binary(), binary(), binary(), binary()) -> ok | {error, any()}. -callback disable(binary(), binary(), binary()) -> ok | {error, any()}. -callback list(binary(), binary()) -> [{binary(), binary()}]. is_carbon_copy(Packet) -> is_carbon_copy(Packet, <<"sent">>) orelse is_carbon_copy(Packet, <<"received">>). is_carbon_copy(Packet, Direction) -> case fxml:get_subtag(Packet, Direction) of #xmlel{name = Direction, attrs = Attrs} -> case fxml:get_attr_s(<<"xmlns">>, Attrs) of ?NS_CARBONS_2 -> true; ?NS_CARBONS_1 -> true; _ -> false end; _ -> false end. start(Host, Opts) -> IQDisc = gen_mod:get_opt(iqdisc, Opts,fun gen_iq_handler:check_type/1, one_queue), mod_disco:register_feature(Host, ?NS_CARBONS_1), mod_disco:register_feature(Host, ?NS_CARBONS_2), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:init(Host, Opts), ejabberd_hooks:add(unset_presence_hook,Host, ?MODULE, remove_connection, 10), %% why priority 89: to define clearly that we must run BEFORE mod_logdb hook (90) ejabberd_hooks:add(user_send_packet,Host, ?MODULE, user_send_packet, 89), ejabberd_hooks:add(user_receive_packet,Host, ?MODULE, user_receive_packet, 89), gen_iq_handler:add_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_2, ?MODULE, iq_handler2, IQDisc), gen_iq_handler:add_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_1, ?MODULE, iq_handler1, IQDisc). stop(Host) -> gen_iq_handler:remove_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_1), gen_iq_handler:remove_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_2), mod_disco:unregister_feature(Host, ?NS_CARBONS_2), mod_disco:unregister_feature(Host, ?NS_CARBONS_1), %% why priority 89: to define clearly that we must run BEFORE mod_logdb hook (90) ejabberd_hooks:delete(user_send_packet,Host, ?MODULE, user_send_packet, 89), ejabberd_hooks:delete(user_receive_packet,Host, ?MODULE, user_receive_packet, 89), ejabberd_hooks:delete(unset_presence_hook,Host, ?MODULE, remove_connection, 10). iq_handler2(From, To, IQ) -> iq_handler(From, To, IQ, ?NS_CARBONS_2). iq_handler1(From, To, IQ) -> iq_handler(From, To, IQ, ?NS_CARBONS_1). iq_handler(From, _To, #iq{type=set, lang = Lang, sub_el = #xmlel{name = Operation} = SubEl} = IQ, CC)-> ?DEBUG("carbons IQ received: ~p", [IQ]), {U, S, R} = jid:tolower(From), Result = case Operation of <<"enable">>-> ?INFO_MSG("carbons enabled for user ~s@~s/~s", [U,S,R]), enable(S,U,R,CC); <<"disable">>-> ?INFO_MSG("carbons disabled for user ~s@~s/~s", [U,S,R]), disable(S, U, R) end, case Result of ok -> ?DEBUG("carbons IQ result: ok", []), IQ#iq{type=result, sub_el=[]}; {error,_Error} -> ?ERROR_MSG("Error enabling / disabling carbons: ~p", [Result]), Txt = <<"Database failure">>, IQ#iq{type=error,sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]} end; iq_handler(_From, _To, #iq{lang = Lang, sub_el = SubEl} = IQ, _CC)-> Txt = <<"Value 'get' of 'type' attribute is not allowed">>, IQ#iq{type=error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]}. user_send_packet(Packet, _C2SState, From, To) -> check_and_forward(From, To, Packet, sent). user_receive_packet(Packet, _C2SState, JID, _From, To) -> check_and_forward(JID, To, Packet, received). % Modified from original version: % - registered to the user_send_packet hook, to be called only once even for multicast % - do not support "private" message mode, and do not modify the original packet in any way % - we also replicate "read" notifications check_and_forward(JID, To, Packet, Direction)-> case is_chat_message(Packet) andalso fxml:get_subtag(Packet, <<"private">>) == false andalso fxml:get_subtag(Packet, <<"no-copy">>) == false of true -> case is_carbon_copy(Packet) of false -> send_copies(JID, To, Packet, Direction), Packet; true -> %% stop the hook chain, we don't want logging modules to duplicates %% this message {stop, Packet} end; _ -> Packet end. remove_connection(User, Server, Resource, _Status)-> disable(Server, User, Resource), ok. %%% Internal %% Direction = received | sent send_copies(JID, To, Packet, Direction)-> {U, S, R} = jid:tolower(JID), PrioRes = ejabberd_sm:get_user_present_resources(U, S), {_, AvailRs} = lists:unzip(PrioRes), {MaxPrio, MaxRes} = case catch lists:max(PrioRes) of {Prio, Res} -> {Prio, Res}; _ -> {0, undefined} end, %% unavailable resources are handled like bare JIDs IsBareTo = case {Direction, To} of {received, #jid{lresource = <<>>}} -> true; {received, #jid{lresource = LRes}} -> not lists:member(LRes, AvailRs); _ -> false end, %% list of JIDs that should receive a carbon copy of this message (excluding the %% receiver(s) of the original message TargetJIDs = case {IsBareTo, R} of {true, MaxRes} -> OrigTo = fun(Res) -> lists:member({MaxPrio, Res}, PrioRes) end, [ {jid:make({U, S, CCRes}), CC_Version} || {CCRes, CC_Version} <- list(U, S), lists:member(CCRes, AvailRs), not OrigTo(CCRes) ]; {true, _} -> %% The message was sent to our bare JID, and we currently have %% multiple resources with the same highest priority, so the session %% manager routes the message to each of them. We create carbon %% copies only from one of those resources (the one where R equals %% MaxRes) in order to avoid duplicates. []; {false, _} -> [ {jid:make({U, S, CCRes}), CC_Version} || {CCRes, CC_Version} <- list(U, S), lists:member(CCRes, AvailRs), CCRes /= R ] %TargetJIDs = lists:delete(JID, [ jid:make({U, S, CCRes}) || CCRes <- list(U, S) ]), end, lists:map(fun({Dest,Version}) -> {_, _, Resource} = jid:tolower(Dest), ?DEBUG("Sending: ~p =/= ~p", [R, Resource]), Sender = jid:make({U, S, <<>>}), %{xmlelement, N, A, C} = Packet, New = build_forward_packet(JID, Packet, Sender, Dest, Direction, Version), ejabberd_router:route(Sender, Dest, New) end, TargetJIDs), ok. build_forward_packet(JID, Packet, Sender, Dest, Direction, ?NS_CARBONS_2) -> #xmlel{name = <<"message">>, attrs = [{<<"xmlns">>, <<"jabber:client">>}, {<<"type">>, message_type(Packet)}, {<<"from">>, jid:to_string(Sender)}, {<<"to">>, jid:to_string(Dest)}], children = [ #xmlel{name = list_to_binary(atom_to_list(Direction)), attrs = [{<<"xmlns">>, ?NS_CARBONS_2}], children = [ #xmlel{name = <<"forwarded">>, attrs = [{<<"xmlns">>, ?NS_FORWARD}], children = [ complete_packet(JID, Packet, Direction)]} ]} ]}; build_forward_packet(JID, Packet, Sender, Dest, Direction, ?NS_CARBONS_1) -> #xmlel{name = <<"message">>, attrs = [{<<"xmlns">>, <<"jabber:client">>}, {<<"type">>, message_type(Packet)}, {<<"from">>, jid:to_string(Sender)}, {<<"to">>, jid:to_string(Dest)}], children = [ #xmlel{name = list_to_binary(atom_to_list(Direction)), attrs = [{<<"xmlns">>, ?NS_CARBONS_1}]}, #xmlel{name = <<"forwarded">>, attrs = [{<<"xmlns">>, ?NS_FORWARD}], children = [complete_packet(JID, Packet, Direction)]} ]}. enable(Host, U, R, CC)-> ?DEBUG("enabling for ~p", [U]), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:enable(U, Host, R, CC). disable(Host, U, R)-> ?DEBUG("disabling for ~p", [U]), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:disable(U, Host, R). complete_packet(From, #xmlel{name = <<"message">>, attrs = OrigAttrs} = Packet, sent) -> %% if this is a packet sent by user on this host, then Packet doesn't %% include the 'from' attribute. We must add it. Attrs = lists:keystore(<<"xmlns">>, 1, OrigAttrs, {<<"xmlns">>, <<"jabber:client">>}), case proplists:get_value(<<"from">>, Attrs) of undefined -> Packet#xmlel{attrs = [{<<"from">>, jid:to_string(From)}|Attrs]}; _ -> Packet#xmlel{attrs = Attrs} end; complete_packet(_From, #xmlel{name = <<"message">>, attrs=OrigAttrs} = Packet, received) -> Attrs = lists:keystore(<<"xmlns">>, 1, OrigAttrs, {<<"xmlns">>, <<"jabber:client">>}), Packet#xmlel{attrs = Attrs}. message_type(#xmlel{attrs = Attrs}) -> case fxml:get_attr(<<"type">>, Attrs) of {value, Type} -> Type; false -> <<"normal">> end. is_chat_message(#xmlel{name = <<"message">>} = Packet) -> case message_type(Packet) of <<"chat">> -> true; <<"normal">> -> has_non_empty_body(Packet); _ -> false end; is_chat_message(_Packet) -> false. has_non_empty_body(Packet) -> fxml:get_subtag_cdata(Packet, <<"body">>) =/= <<"">>. %% list {resource, cc_version} with carbons enabled for given user and host list(User, Server) -> Mod = gen_mod:db_mod(Server, ?MODULE), Mod:list(User, Server). mod_opt_type(iqdisc) -> fun gen_iq_handler:check_type/1; mod_opt_type(db_type) -> fun(internal) -> mnesia; (mnesia) -> mnesia end; mod_opt_type(_) -> [db_type, iqdisc].